LONDON, May 27 (Xinhua) -- A butterfly that became extinct in England more than 40 years ago was reintroduced recently as part of an 8-million-pound initiative to save the nation's most endangered species.

The mottled golden wings of the chequered skipper butterflies were once a common sight along the edge of forest tracks until they disappeared in 1976 after decades of habitat loss.

Lepidopterists trapped swarms of adult butterflies in Belgium this week and transported them to England ahead of their release in the Rockingham Forest, Northamptonshire.

Local press report said that 50 of the species were released in a secret location in Rockingham Forest.

A small number of the chequered skippers had survived in Scotland, but scientists said that conditions in Belgium were closer to their intended home. Both sites have an abundance of false brome, a type of grass, which their caterpillars feed on.

Butterfly Conservation, which runs the project, said it was an "important milestone for conservation."

It said that the recent release is the first in a series of planned releases, but the precise locations would remain secret until the population had taken hold.